Dwarf olive snails
Dwarf olive snails | ||||||||||||
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Olivella biplicata with snowplow-like propodium |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Olivellidae | ||||||||||||
Troschel , 1869 |
The pygmy olive snails (Olivellidae) are a family of small, exclusively marine snails that live mainly in warmer seas.
features
The olive-shaped shells of the dwarf olive snails have a smooth, shiny surface and are often provided with a color pattern. The length of the case mouth takes up only a third to half of the total length of the case. In contrast to the olive snails , the dwarf olive snails have no antennae and no eyes, and they also lack parotid glands. The operculum is usually horny and closes the entire case mouth.
Distribution and way of life
Most species of pygmy olive snail are found in tropical and subtropical waters of North and South America , and some in the temperate climate of North America. Some species live on the coasts of Australia .
The dwarf olive snails inhabit sandy and muddy subsoil as soft-bottom dwellers, where they feed on meiofauna and microfauna , including foraminifera . While the American species can be found in the intertidal zone and below, the Australian species live below the intertidal zone to a depth of about 100 meters.
Systematics
According to Bouchet & Rocroi (2005), the Olivellidae family together with the olive snail family (Olividae) form the superfamily Olivoidea . The dwarf olive snails belong to three genera:
- Janaoliva Sterba & Lorenz, 2005
- Olivella Swainson , 1831
- Olivellopsis Thiele, 1929
The following genera are synonyms :
- Dactylidia H. Adams & A. Adams, 1853: Synonym by Olivella Swainson, 1831
- Janoliva [sic]: Synonym from Janaoliva Sterba & Lorenz, 2005
The dwarf olive snails are still counted by Ponder & Lindberg (1997) to the family Olividae within the superfamily Muricoidea. Bouchet & Rocroi (2005) already run them as a separate family in the superfamily Olivoidea.
literature
- Philippe Bouchet, Jean-Pierre Rocroi: Part 2. Working classification of the Gastropoda . Malacologia, 47: 239-283, Ann Arbor 2005 ISSN 0076-2997
- Victor Millard: Classification of the Mollusca. A Classification of World Wide Mollusca . Rhine Road, South Africa 1997 ISBN 0-620-21261-6
- Frank Riedel: Origin and evolution of the "higher" Caenogastropoda . Berliner Geoscientific Abhandlungen, Series E, Volume 32, Berlin 2000, 240 pages, ISBN 3-89582-077-6 .
- Winston Ponder, David Lindberg, Towards a phylogeny of gastropod molluscs; an analysis using morphological characters . Zoological Journal of the Linnean Society, 119: 83-265, London 1997 ISSN 0024-4082